Transmission



Jan. 31, 1933. D, L, Lows 1 1,895,888

TRANSMISSION Filed Jan. 24, 1930 3 Sheets-Sheet 1 v /0 8 65 J 62 58 0-9 8 6 Z 66 1 3; Sheets-Sheet 2 WE L7H DelbsizLlo/[s Jan. 31, 1933.

Filed Jan. 24, 1950 L 8 1 F. 5 5 a M. $8 2 5 1 7 g M: 8 4 9% 6a. M/Y W. 5 p w 5 w M M W w 5 E M z Z J.

D. L. LOTTS TRANSMISSION Filed Jan. 24, 1930 we as. Delia! Z 102?;

I 14.7 M wi ibgfi J I! 7 E Jan. 31, 1933.

Patented Jan. 31 1933 ITED STATES PATENT O E i amien [1,. Lo T s, OF CHICAGO, rumors, AssIGNoR, B'Y DIRECT AN D MESH]: 'AssIGNMENTs; To

' ennnrmn RESEARCH CORPORATION or ILLI vors CQRPOBAT'IQNK OF CHICAGO, ILLINOIS,i A

r TRA'NsMiss'roiv" a Applicatio'nifiled January 24,1930, Serial Nb. 423,030. j Y t v This invention relates to an improved simplified type of transmission adapted to be used between a driving shaft and a driven shaft and obviating the use of the customary clutch mechanism and gear shifting ordinarily required in transmitting a drive from adriving shaft toa driven' shaft to rotate the driven shaft at different ratesofspeed. t

It is an object of this inventionto'provide a power transmission device of improved and. simplified form adapted for the transmission of variable speeds vfrom a driving shaft to a driven shaft through the medium of intermeshing 'worm'members and adjustable means'for changing the relative speed of the worm members with respect toone another'to create a planetary gear action vbetween the worm members to causea drive to be'transmitted from a driving shaft to a driven shaft proportionate to the relative difference in speed between the worm members. t v i a It is also an object of this invention to provide an improved type. or" power transmission between a-driving member and a driven member through the medium of intermesh- .ing worm members disposed in a transmission-casing connecting the driving member with the driven member and having lever controlled relatively shiftable helical gear control members for varying the speed of the worm'members with respect to one another and produce a relative travelling movement of said worm members relative to'one another. to permit variable speeds to be transmitted to the driven member through the locking action between the worm members. v lt'is'a further object of this inventionto provide an improved type of power transmission between a driving member and a driven member by means of worm members rotatably engaging one another at the'same rate of-speed and adaptedto have the relafive speed thereof varied by the relative shifting of intermeshing helical gears tov per- .niita variable drive to betransmitted to the driven member. r v

vStill another-object of the invention is ito provide a transmission fortransmitting a variable speed. from i a driving member .to :a

driven member through worm members i one of which is adapted to have-the speed thereof varied with respectto'the other by means of relativelyxadjustable intermeshingjgears adapted to be adjusted to vary the torque between the worm members'to producerelativetravel therebetween and a transmission of the drive'from the drivingto the driven member commensurate with the changes in 1 the rotating speed of the worm members. It is furthermore an object of this invention to provide an improved transmission wherein a pair'ofshafts are adapted to be connected by a transmission housing through the medium of worm members'rotatably engaging one'another and-adapted tohave the speedofrotation between one another varied througlr helical gear control mechanism carriedby thehousing and the driven shaftto be rotated at arate of speed proportionate to the torque produced between the worm members to permit the speed, of thevdriven member to beincreased up to the speed. of the driving member when one of the worm members is completely locked with the other and rotates therewith. y 1 1 It is an important object of this invention to provide an improved simplified type of transmission between a driving member and y a driven member through the medium of a housing. and Worm members therein having relative 'rotative movement with respect to oneanother and adapted'to havethe relative rotative speed thereb'etween varied through a gear trainl'controlled'by'the relative shifting movement of a master helical gearwith respect to auxiliary helical gears; whereby the driving force transmitted from the drivingmemberto the housing or driven member is directly "dependent upon the relative change of rotation between the worm members and the relative rate of travel of one of the worm members with" respect to the other. 7 Other and further objects of this invention will be apparentrfrom the'disclosuresin the m specification and the accompanying drawings. 2 g a r The invention (in apreferred form) is'illustrated in the; drawingsand' hereinafter F10 moreffully described. a

9 of the transmission taken On the drawings:

Figure 1 is a side elevation of an improved,

transmission embodying the principles of this invention.

Figure 2 is an enlarged side elevation of the transmission with the side cover plate removed. V

Figure 3 is a fragmentary detailed section taken on line TIL-III of Figure 2 with parts shown in elevation. Figure 4 is an tailed section taken on line IV'.IV of Figure 2 with parts shown in elevation.

Figure 5 is an enlarged fragmentary lon'-.

gitudinal sectional view ofv the transmission taken on line VV-of-Figure 1 withparts shown in elevation and with the side closure plates of thetransmission housing omitted.

Figure 16 is a longitudinal sectional view on line VI-VI of Figure 5 with parts shown in elevation.

:Figure 7 is :acdeta-iled sectionalview of the transmissionjtaken on line-VII-VII of Fig- "ure 6.

Figure 8 is a tra sverse detailed sectional view of the transmission taken :on line VIII? .VIII of Figure 6. .8

having transmission mechanisms enclosed therein and'adapted to be'governed by a control mechanism associated with the driven shaft 2 and with the transmission housing as hereinafter more fully described. -The transmissionhousing while indicated and described as of a rectangular configuration may be ofa cylindrical type or any other desired selected form. In the present showing the casing orhousing comprises a pair. of end walls3 and 4 which are held inseparated spaced relation by means of a pair of parallel partition plates or inside walls 5 which are adapted to'be rigidly held in position by means of retaining bolts'6 orother suitable means. The partition plates 5 divide the in -V terior of thecasing or housing into two side chambers 7 and an intermediate chamber 8. Two pair of side'closure plates 9 and- 10 are provided to close the chambers 7 and 8 and are adapted to be securedin position'by means of retaining screws 11 or other suitable means.

Keyed. orotherwise secured" on driving shaft 1 withinthemain or intermediate ,ch'amber'8 and adj acent the inner surface of the housing end wall 3 isa worm g ar-12 in the present showing having'twelve teeth positioned at" an angle of to'meshorfunction with 15 threads ofa pair of worms 13 which are positioned in parallel relation on enlarged fragmentary de the worms 18 is keyed or otherwise secured on a shaft 14 havingreduced bearing shanks or sections 15 which are journaled in the partition plates 5 and have engaged therearound ball thrust bearings 16 which are partly seated in suitablerecesses provided in the inner surfaces of the partition walls 5 as clearlyillustrated in Figure 4. The ball thrust bearings 16are so positioned to coact with the ends of the worms 13'to receive the end thrust imparted to the worms; 1

One of the bearing shanks 15 of the shaft 14 is provided with a reduced shaft extension 17 which projects beyond the outer surface of the respective partition wall or plate 5 and haskeyed or otherwise secured thereon a spur gear 18 which is; spaced from the par,- tition wall-5 bymeans of aspacingwasher 19. Positioned to the outside of the spur18 and against the outer hend of the stud shaft extension 17 is, aretaining'washer '20 which is held imposition by: means of .ascrew 21 whlch pro ects through the retainingwasher 'and is threaded into a threadedrecess provided in the end ofthe shaft extension 17 as.

clearly illustrated in Figure 4. 8

, The spur gears 18 are located so that one of the spur gears is positioned to the outside of one of the partition walls 5 while the spur gear 18 for thesecond worm is positionedto the outside ofthe second partition wall 5 as clearly illustrated in Figure 8; Each of'the worm spur gears 18 has meshingtherewith an intermediate spur gear 22 which idles or rotates on a bolt shaft 23 which projects through the intermediate gear 22 and has the inner threadedv end thereof engaged in the partition wall 5. Meshing with the intermediate spur gear 22 is a spur gear 24 which completes the chain-ofspur gears, one set of which is mounted to the outside of each of the partition plates in the arrangement illustrated in Flgure 2. 8

The spur gear 24 is mounted on the outer pro' ectlng end of an enlarged shaft bearing section or shank 25 the outer end'of which is provided with a diametrical notch orslot 26 in which the shank or body portion'of an I-bar or key 27 is seated.- Theends' or heads of the I-bar 27 are providedwith apertures forthe reception of screws 28 which engage in screw slots in the spur gear 24. Projecting through a diametric passage or opening in the outer end of the slotted shaft shank 25 is a retaining pin 29 which serves to lock the spur gear 24 on, the shaft shank 2 5. P0

sitioned on the shaft shank 25 adjacent the inner side of the spur gear "24 is a washer ring 30 against which the'outer end of a plu- 'rality of coiled springs 31 are adapted to seat.

The inner ends of the coiled springs 31 seat" in pockets or recesses 32 provided in the out- "er side of the partition plate'onwall 5 around the shaftshank 25 as illustrated} in Figure 3.

' The: shaft bearing shank extension is integrally formed on one end of an auxiliary helical gear supporting shaft 33 the opposite end of which is reduced in diameter to provide a shaft bearing shank section 34 which projects through a bearing opening in the op.- posite partition wall 5 and has the outer end thereof threaded at 35 to receive'an internally' threaded retaining ring or washer 36 threaded thereon to limitthe shifting of the auxiliary shaft 33 inwardly from-the threaded end35 of said shaft. To hold the retaining ring or washer 36 locked in position on the threaded portion 35 of the shaft 33 a lock washer or'nut 37 is engaged on the threaded extension 35 of the shaft to the outside; of the lock ring or washer 36 as clearlyillustrated in Figure 5. Keyed orotherwise secured onthe auxiliary shaft 33 between the partition walls 5 is a secondary or auxiliary helical gear 38 the teeth of-which-are out at a helix angle of 45. i

As illustrated in Figure 7 there are two auxiliary helical gears 38 mounted on'the parallel auxiliary shafts 33 disposed on opposite sides and at right angles to the main driving shaft 1. "The auxiliary helical gears 38 are in mesh with the 45 angle teeth of a main large helical gear 39 which is slidably keyed by means of a key 40 on the main driving. shaft 1 within the housing chamber 8 between the inner end of the worm gear 12 and a bearing block 41 secured on the inner sideof the housing end wall 4 by means of retaining screws 42 or other suitable means as clearly illustratedin Figure 6. The main helical gear 39 is adapted to be shifted with respect to the auxiliary helical gears 38 for the purpose of changing the relative speed of rotation between theworms 13 and the worm gear 12 to control the driving torque between the driving shaft 1 and the-driven shaft 2. The main helical control gear39 is provided with a diametrical opening or slot 43 in one end thereof for the purpose of rece ving a pin or peg 44 which is adapted to fit in segmental grooves provided within the helical gear 39 so that the pin 44 may be positioned at substantially right angle toithe inlet slot 43 to hold the pin locked in engagement with the main helical gear 39 to permit shifting of the same on the main driving sh aft 1. V

The inner end of the main driving shaft 1 projects through the bearing block or member 41 and into an axial chamber or opening 45 provided in the inner end of the driven shaft 2 the end of which extends into an opening provided in the transmission end housing plate 4 as clearly illustrated in Figures and 6. The inner end of thedriving shaft 1 is provided withan axial passageor recess 46 through whichthespin 44 projects with the. projecting portion of the pin passing through a diametric'guide slot 47 provided V in' the driving; shaft 1 to afford an arrange,

ment whereby the mainfhelicalhgear 39 may .be shifted longitudinallyon the driving shaft 1 by means of a plunger or rod I43u'which slidably projects axially into the passage 46I'pro-V videcl in the end of the driving shaft 1.- -The pin 44 projects through 'aldiametric-passage provided in the inner end of the. plunger rod 48 as clearly illustrated .in Figures 5-and 6.

The plunger rod 48 projects out. of the; end of ments 501 are slidably seated tozpermit the 7 same to rotate in they groove of :the; plunger head. The ring sectionsfor' curved segments 50 aresecuredby retainingscrews 51 or other suitable means circumferenti ally within arece ssf52 provided in one end of a shiftcore or slide member 53 which is slidably engaged in an axial chamber or passage 54 provided in the driven shaft 2 to the inside of the axial chamber oropening 45. I Engageddiametri cally through an opening in the shift core 53 is a control pin or bar 55 the ends of-which projectthrougha pair of diametricall'yopjpositeslots 56 p-rovidedin the inner end .of the driven shaft 2. The ends oftheoontrol pin 55 which project through the slots '56 of the driven shaft project into achamber or recess 57 provided-in one end offiashiftable sleeve or collar58 which is slidablyengaged on the-end section ofthe' driven shaft 2% clearly illustrated inFigures5 and6. {Engaged in the outer end of the shiftable, sleeve or collar 58, by means of screws '59 or other suitable devices is a retaining ring or collar To facilitate shifting of theshifter collar or sleeve 58 on the driven shaft 2,1said1shift collar has pivotally connected to opposite sides thereof a pair .of connecting rodsor links 61,:the outer ends of which are pivotally connected to "opposite sides ofa yokeor fork 62 having integrally formed thereon an arm or lever 63 to facilitate operation of the fork. The fork 62 is pivoted on pivotxpins 64' mounted diametrically opposite-one an other on a collar'or sleeve 65 engagedon the driven shaft 2 to the outside of the shift collar or sleeve 58 as clearly illustrated in Figure 1. a. i

The lever supporting collar or sleeve 65 has the driven shaft 2 journalled therein and is adapted-to be rigidly held'in position by any suitable means when the improved transmis sion is coupled up for use between a driving shaft 1 and a driven ishaft2 OILOIIG'OIlCl of which a transmission housing is adapted to be rigidly secured by suitable clampingor retaining means. Secured on the, driving shaft 1 to rthev outside- 0f the transmission housing endplate 3i-isa retainingflor stop collar 66 for properly holding the transmisg sion hou'sin giand the driving and driven shafts in proper coacting relation.

" The operation is as followsz -The improved transmission is 'adaptedL-to be used foritransmitting a drive from a drlving member to a driven member without the use ofthe customary clutch mechanism and without requiring the shifting of gears for driving the driven member from the driving memberat variable speeds. The improved transmission may be used as a transmission Iforpower in motorvehicles, in machine shops or in any desired position or combination wherein. it is necessary to'transmit a drivingpower from a dr1v1ng member or shaft to a driven member or shaftf I -As illustrated in Figure 6 the transmission housin is rigidly keyed tothe driven shaft 2 on w ich the control mechanism is mount-.

ed for governing the operation of the meshing helical control gears 38 and 39, the relatively adjustment of which regulatesxthe speed of rotation ofthe-worms 13 relative to the rotativespeed of the worm gear-1 2, wh1ch is keyed to androtates with the dr1v1ng shaft or memberl. The transmission embraces the housing or casing which is connected between the driving and driven shafts and encloses the-worm gear 12 on the driving shaft .1 and the co-acting intermeshing worms 13 which are rotatably mounted in thehousing and are controlled by means of the adjustment of the main helical gear 39' with respect to the auxiliary'helical gears 38 which are mounted on the rotatable and shiftable auxiliary shafts 33. i The shafts 33 are connected. with the worm bythe two sets of spur gear's the speed of which govern the rotation of the worms 13 relative to the speed of rotation of the worm gear 12 to vary the torque between the worms and the worm gear to determine the rate of travel of the worms around the worm gear to permit anydegree of speed to be imparted from the driving shaft 1 to'the driven shaft2 from a stationary or stopped position ofsa id shaft 2 to a'rate of speed equal to the speedof the drivingshaft '1 depending upon the adjustment of the control lever 63 which governs the relative positionof the main helical control gear 39 with respect to the auxiliary helical gears 38. I 1

WVhen-the control lever 63 is in a'neutral position similar to that illustratedin Figure 1 the maincontrol helical gear 39 is sopositioned with respect to the auxiliary gears 38 that the spur gear trains permit the worms 13 to rotate at the same rate of rotational "speed as the worm gear'12 and the driving shaft l-so that there is no relative travel of the worms around the worm gear, conse- "quently causingno drive from-the driving shaft 1 to be transmitted to the transmission housing and the drivenshaft 2" connected therewith It will thus'befseen thatwhen thel'control lever isin neutral position that stationary :58. to slide outwardly on the driven shaft 2" thereby causing the pin 55 to slide in the grooves 56 of the :driven': shaft'permitting the connectingrod section 53 to slide in the shaft recess 54 and cause aipullto be exerted on the connecting shaft section 48 to cause the same to slide outwardly with respect to the driven-shaft 2 whereby the pin f in the connecting shaft section 48slides' outwardly with "respect to the driving shaft 1' thereby c'ausing'the main control helicalgear 39 to be shifted or slidably moved outwardly on the driving shaft 1 in a direction approaching the end of the driven shaft 2 so that the relative .posit ion'of the main helical gear 39 with respect to the'auxiliary helical gears 38 is'c'hanged. The shifting of the main helical gear 39 with respect to the auxiliary helical gears 38-varies thedrivingtorque between said helical gears and causes the auxiliary helical gears and the shafts 33 supporting the same to be rotated at a reduced rate o-f-speed so that the speed transmitted to the spur gear trains is proportionately reduced,consequently causing the speed of rotation of the worms 13 to be also proportionately reduced so that the worms rotate at aslower rate of speed than the speed ofrotat-ion of'the worm gear 12/ This change in the relative speedof rotation'of the worms with respect to the worm 7 gear '12 produces a torque between the mesh-- ing worms and the worm gear therebycaus ing the wormsduring' their rotation to travel circumferentially around the worm gear 12 at arate of speed dependingupon the rela-.

tiveadjustment of the main helical gear 39 worm gear is compensated for by the ball thrust bearings 16. Any end thrusts which are transmitted to the auxiliary shafts 33 on which the auxiliaryhelical gears 38 are mounted is compensated for by the springs 31 which are associatedwith the spurgears with respect to the auxiliary helical gears 38. Any end thrusts which may be produced due to the travel of the worms around the 24 so that there'will be no difference in the 3 relative drives transmitted from one of the 33 to the other worm 13. An arrangement has 'thus been provided whereby the drive transmitted to both of the worms 13 isalshafts 33 to its correspondingworm 13 from that'transmitted by the other auxiliary'shaft all.

mamas.

ways substantially the same, thereby produc-- ing a balanced drive connection of the two worms 13with respectto the worm gear12; Any unevenness in the co-acting relation of the two worms 13 with the worm gear 12 may also be compensated for by. the adjust.

ment of the I-bars 27 with. respect to the spur gears 24:. It will thus be noted that two, ar-' transmission mechanism consisting of a properly balanced or adjustable gearxand worm group unit which co-operates with the worm gear on the drivingshaft.

- The outward movement'of the master helical gear 39 outwardly at right angles with respect to the helical gears 38 causes a corresponding reduction in the speed of rotation ofthe worms 1?) with respect to the wormgear 12 so. that with the reduction in the speed of. rotation of theworrns13 the rate of travel of said worms 13 around theworm gear 12 is proportionately increased as is also the speed of rotation of the transmission housing and the driven shaft 2 connected therewith. The speed of rotation of the worms:

13xis adapted to be decreased until the rate.

of travel of the worms around the worm gear 12 becomes equal to the speed of rotation 'of the driving shaft 1 and the worm gear 12' producing a condition. wherein the worms 13.

are lockedwith the worm gear 12 simultaneously causing a locking of the spur gears and the helical gears, thereby producinga' condition ofhigh speed transmission wherem the speed of rotation of the driving shaft l is transmitted directly to the lockedtra nsmission and to the driven shaft 7 It will thus be seen that the improved transmission permits a variable speed. to be transmitted from the driving shaft 1 to the driven shaft 2 depending'directly upon the adjustment of the main helical gear 39 with respect to the auxiliary helical gears 38 by the shifting of the control sleeve 01'' collar 58 through the medium of the links 61 operable by the control lever 63 and the controlforlr' 62 which is pivotally mounted on the sta-' tionary supporting collar 65 on which the controllever is mounted.

While a rectangularhousing is illustratedand described in connection with the gear and worm mechanism ofthe transmission it will,of course,be understood that a cylindrical housing orany other design of transmission housing may be used. 1

Attention' is also called to the fact that the lever control mechanisms illustrated and described in connection with Figures 1, 5 and 6 of the drawings may. of course, be varied in construction to suit the particular adaptation to V which i the improved transmission is It will, ous other detailsof construction may be varied through a wide rangewithout depart ing from the principles of this invention and it is therefore not the purpose to limit the patent granted-hereon otherwise than necessitated by the scope of thea ppended claims. I claim as my invention: 1. A transmission comprising a driving shaft, a driven shaft, a housing secured to said driven shaft andhaving the driving shaft journalled therein, a worm gear in said housing secured tosaid driving shaft, a worm. rotatably supported .in said housing and meshing with said worm gear, a main helical.

gear slidably mountedon said drivingshaft,

an auxiliary helical gear meshing therewith, means'connecting the same with saidiform, and a. control for shifting said main helical gear with respect to said auxiliary helical gear for varying the speed of rotation of the worm withrespect to the speed of rotation of the worm gear to permit a variable speedpto be transmitted from the driving shaft to -said driven shaft. u l i r 2. A power 1 transmission .comprising adriving shaft, a driven shaft, a housing secured to said driven shaft and'having one end of the driving shaft journalled therein, a worm mechanism in said housing and connected-with said driving shaft, and relatively adjustable helical gear members for govern-.. ingthe operation of the worm mechanism topermit a drive to be transmitted fronr-the driving shaft to said housing and said driven shaft 1 3. A power transmission comprising a. driving shaft, adrivenshaft axially aligned therewith, a housing supported on .:said driven shafta nd enclosing one end of said driving shaft, a worm gear secured on said driving shaft within said housing, a worm. rotatably mounted in said housing and meshing with said worm gear, a'helical. gear slidably: keyed on said drivingshaft within said of course, be understood that 'vari-' housing, an auxiliary helical gear co-acting worm-gear and permit a variable drive to be transmitted from the driving shaft to said driven shaft.

4. A power transmission comprising a driving member,'a driven member, a worm gear secured on the driving member, a rotatable worm meshing with said wormgear and mounted to permit the same to travel circumferentially around the worm gear, and helical gears mounted to permit one to be housing connecting the same, a worm gear 1 5 gear control means comprisinga gear con-.

secured on the driving member to rotate therewith, a worm rotatably supported in said housing and having rotatablemeshing engagement with said worm gear, and helical ne'cted to" saiddriving member to rotate therewith and axially movable relative there-= to for changing the speed of rotation of the worm with respect to the 'worm gear to permit a variable speed to'be transmitted from thedriving member to the driven member.

6; "A power transmission comprlsing ax-- ially aligned driving and driven members, a housing-secured to sa1d driven member, a

, worm gear secured'on thedriving member within said housing, a worm rotatably sup-f ported in said housing having rotatable interfitting engagement with said worm gear, a main control helical gear' shiftably keyed on saiddriving member within said'housing, an auxiliary helical gear meshingiwithsaid .main' helical gear, a gear train connecting said auxiliary helical gear with said worm, and control means connected withthedrlven V member and with themain helical gear on said driving member to permit'the main helical ear to be shifted with respect to the auxi iary helical gearito vary the speed of rotation of the worm with respect to the.

wormgear to permit-a variable drive to be transmitted from the driving member to said housing and the driven memberI 1 7. A transmission comprising adriving mechanism, a driven; mechanism," a worm gear secured on the driving mechanism, a worm. rotatably supported by said driven mechanism and havingrotatablemeshing engagement with-the worm gear, and a control mechanlsm includlng helical gears 1ntermeshing at right angles with respect to one another'and connected withtlie worm for varying the relative speed of.rotationfthereof with respect to the worm' gear to causea relative circumferential travel of the worm around the worm gear and the transmission of a variable speed from the driving mechanism to said driven mechanism.

8. A power transmission comprising a driving member, a driven member, a housing supported'on saidid'riven memberand enclosingone end of said driving-member, a worm gear secured on said driving member within said housing, a worm rotatably supported in said housing and having rotatable 1 meshing engagement withsaid worm gear, a

gear train connected with said Worm and support d in said housing, an auxiliary; shaft journalled in saidhousing and connected withsaid gear train, an auxiliaryhelical gear secured on said auxiliary shaft, a :mainhelical gear shiftably keyed on said driving a member within said housing and having meshing engagement with said auxiliary.

helical gear, and a'controlmechanism con-' nected-with' said mainhelical gear and'operable from theexterior of said housingto cause themain helical gear to be shifted'with respect to the auxiliary helical gear to vary the speed of rotation-0f the wormwith re s'pect to the Worm gear to cause a drive from the driving member to be transmitted to the driven member at aspeed proportional to the relative change in=rotationalspeed between the worm and said worm gear:

9. A power] transmission comprising a driving member, a driven men1ber, a'ihou sing; secured to sa1d driven member-andwurnalled on said driving member, acwo'rm gearlse cured on said driving 'memberwithin said: housing, a plurality of worms rotatably mounted. in said housing an d-having rotat able meshing engagement with said worm gear, a plurality of auxiliary sliaftsjour nailed in'saidhousing, an auxiliary helical gear secured onea'ch of said auxiliary shafts,"

a train of 'intermeshing spur gears between each auxiliary shaft and one of said Worms,

a main helical gearslidably keyed on said driving member within said housingshaving meshing engagement with'said auxili aryiheli-i cal gears, a control sleeve shiftably'mounted,

on the driven member to theoutsideiof said housing, means connecting said c'ontrolsleeve with said'main helical gearQand atone-o1 device connected with said controlsleeve to permit operation thereof and shifting of the main helical gear with respect tothe auxiliary helical gears to cause therelative-speeda of rotation of the worms with respect' to the worm gear to bechanged to permit a variable speed to be transmitted from the-idriving member to'said driven membersv 10. A power .transmlsslon comprisingga driving member, a; driven member-axially engaged with i one end thereof, a housing "rigid ly secured to saiddriven member and jourk nalled on said driving member a worm gear;

in said housing secured on said driving mem her, a plurality of worms rotatably. journalled in said housing and'having rotatable meshing engagement with said. wormgear, a

main helical gear shiftably'keyed onsaid driving 'memberwithin said housing, a -plu-;

* rality of auxiliary helical gears meshing with said main helical gear, auxiliary shafts ournalledin said housing and supportingxsaid auxiliary helical gears, trainsof intermeshing spur gears connecting said auxiliary shafts with said worms,-a controlmchanism connecting said driven member with. said main helical-gear to permit shifting. of the rpoaasa main helical gear with respect to the auxiliary helical gears to vary the speed of rotation of said worms with respect to said worm gear to cause a variable'speed to be transmitted from said driving member to said driven. member, and mechanisms connected with said auxiliary shafts adapted to maintain the worms in equalized working relation with the worm gear.

11. A. power transmission comprising a pair of rotatably interfitting shafts, a housing secured on one of said shafts and journalled on the other of said shafts, a worm gear secured on one of said shafts within said housing, wormsrotatably mounted in said housing and having rotatable intermeshing engagement withsaid worm gear, a main helical gear shiftably keyed on the shaft on which said worm gearis secured, a plurality of auxiliary helical gears meshing with said main helical gear, gear trains connecting said auxiliary helical gears with said worms, a control mechanism connected with said main helical gear to permit the same to be shifted with respect to said auxiliary helical gears to cause the speed of rotation of the worms to be varied with respect to the speed of rotation of the worm gear to permit a variable speed to be transmitted from one of said shafts to the other, and means connected with said gear trains for maintaining the worms in equalized co-acting engagement with said worm gear.

12. A power transmission comprising a driving shaftand a driven shaft, a housing secured on said driven shaft, a worm gear secured on said driving shaft. within said housing, a worm journalled in said housing and meshing with said worm gear, gear mechanisms connecting said driving shaft with said worm, and a control mechanism for shifting one of said gear mechanisms at right angles with respect to the others to cause the speed of rotation of the worm with respect to the worm gear to be varied to cause a variable speed to be transmitted from the driving shaft to the driven shaft.

13. A power transmission comprising a driving member, a driven member, a worm gear secured on the driving member, a worm connected with the driven member and coacting with said worm gear, and helical control members connected with the worm and shiftable one with respect to the other for varying the speed of rotation of the worm with respect to said worm gear to govern the relative travel of said worm around said worm gear to permit a gradual increasing or decreasing rotational drive to be transmitted from the driving member to said driven member.

14. A power transmission comprising a driving member. a driven member, a housing secured on said driven member and journalled around said driving member, a worm gear secured on said drivingmemherwithin said housing, a worm rotatablyf'journalled in said housing and having rotatable meshingengagement with said iwormgear, thrust ball bearings for said worm, inter-meshing spurgears connected with saidv worm, an auxiliary shaft shiftably journalledin said housing and 'supportingone of said spur gears, means connected withthe spur gear. on'said auxiliary shaft tomaintain the worm in proper co-acting relation with the worm gear, an auxiliary helical gear mounted on said auxiliary shaft, a main helical gear meshing with said auxiliary helical gear, said main helical gear having shiftable keyed engagement with said driving member, and a control lever, mechanism associated with the driven member. to. the outside ofisaid housing and connected with said main helical gear to varythe drivingltorquebetween said main helical gear andsaid auxiliary helical gear to cause the speed of' rotation ofthe worm with. respect to the worm gear to be proportionately varied to permita gradual vari ble speed to be. transmitted from the driving member to the driven memberr s 15. A power transmission comprising a driving member, a driven member, a worm gear secured on the driving member,ia worm journalled in the driven member and rotates bly meshing'with said worm gear, means'com nected with said driving member .to-camserotation of the worm, and ahelicalgear control device for adjusting said means to vary the speed of rotation of the worm with respect to the worm gear to cause a variable speed to betransmitted from the driving member to the driven member proportionate to thejrelative change in the speed of rotation of the worm with respect to the rotation of the worm gear.

16. A power transmission comprising a driving member, a driven member, a. housing rigidly secured on said drivenmember and journalled on said driving member, a 15 worm gear secured on said driving member, a 159 worm rotatably meshing with said worm gear, a 45 helical gear slidably keyed on said driving member, a 45 auxiliary helical gear meshing with said main helical gear, a gear train connecting said auxiliary helical gear with said worm, and means for adjusting the main helical gear shiftably at right angles with respect to said auxiliary helical gear to vary the speed of rotation of the worm with respect to the'speed of rotation of said worm gear to permit a variable drive to be transmitted from the driving member to said driven member.

17. A power transmission comprising a driving member, a driven member, meshing worm members one of which is driven by the driving member, gear members connecting thedriven member with said worm members worm memberuwithfrespect to the other to cause a variable drive to be transmitted from the driving member .to the driven member,

and. a control. device connected with one of said gear members to shift the same with respect to the remaininggear members to produce the variable drive." 'Y is -18. Ahtransmission' comprising a driving mechanism and a driven mechanism, means including a Worm and gear connecting said -mech'anisms', and relatively shiftable interfitting gears connected 'With said means and shiftable with respect to one another for changing the relative speed of rotationbetween th'e v vorm and gear members forming said means-to cause a gradually changing variable 1 speed-t0 be transmitted from I the dri yingrmechanis'mto said driven mechanism.

l9. ower i transmission 8 comprising a driv ng member, a-"drlven member, meshmg Worm membersfor effecting a drive between said members, 'agear trainincluding interme'shi'ng worm'gear members; between said d'llvln'g" member and said Worm members,

, and control means for shifting said Worm gear members relatively to one another for changing therelative speed of said orm members to cause 'a'gradually changing variable speed to betrans'mitted from the driving member to the driven member. 1 I

In'tes timonyvvhereof I have hereunto sub-- scribed my name at Chicago, Cook County,

Illinois.

DELBERTL. LOTTS; r 

